To solving with their equation and expression to step by step.
3b/a-2
= -2a+3b/a
The key thing to look for to determine whether a sequence is geometric is to see whether the ratio between consecutive terms - the number I would multiply one term by to get the next - is constant.
By inspection, we see that the fourth answer choice satisfies that, as
Why not the first? We have 
The third choice is not a geometric sequence, but rather an arithmetic sequence, where the difference between consecutive terms is constant. Just to make sure that it isn't geometric, we compute 
The second sequence is not geometric (although it does eventually converge to 1, but not its corresponding series), as 
To solve for the quadratic equation 9x² = 4, we need to recall that the difference between two square can be expressed as the product of their sum and difference or (a² - b²) = (a + b)(a - b).
Thus, we have
9x² = 4
9x² - 4 = 0
(3x)² - (2)² = 0
(3x + 2)(3x - 2) = 0
We now have two linear equations:
3x + 2 = 0 | 3x - 2 = 0
3x = -2 | 3x = 2
x = -2/3 | x = 2/3
Thus, x = +2/3 and -2/3.<span>
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A percentage is simply a special type of fraction with a divisor of 100 and the numerator shown beside the percent sign. So 50% is really 50/100, which reduces to 1/2.